This paper is concerned with the inelastic behavior of axially loaded concrete-filled thin-walled steel tubular columns subjected to local buckling. A nonlinear fiber element analysis program accounting for local buckling effects is developed for predicting the ultimate strength and ductility of concrete-filled thin-walled steel tubular columns. The effects of local buckling are taken into cons...

The nonlinear mechanical response of carbon nanotubes, referred to as their "buckling" behavior, is a major topic in the nanotube research community. Buckling means a deformation process in which a large strain beyond a threshold causes an abrupt change in the strain energy vs. deformation profile. Thus far, much effort has been devoted to analysis of the buckling of nanotubes under various loa...

Carbon nanotubes (CNT) are potentially promising fibers for ultra high strength composites. In order to fully harness the outstanding mechanical properties of carbon nanotubes as fiber reinforcements, it is essential to understand the nature of load transfer between fiber and matrix under various types of loading conditions that include tension, compression, torsion and a combination thereof. I...

First-ply failure (FPF) of composite thin-walled columns and frames is investigated in the buckled structure. Elastic behavior is assumed during the pre-buckling and buckling states, and along part of the post-buckling equilibrium path. The Tsai-Hill criterion is employed to identify failure of one ply at one specific location. The technique of analysis is based on evaluation of the post-buckli...

In this paper, the buckling and vibration behaviour of functionally graded flexoelectric nanobeam is examined. The vibration and buckling formulations of functionally graded nanobeam are developed by using a new theory that’s presented exclusively for flexoelecteric nano-materials. So by considering Von-Karman strain and forming enthalpy equation based on displacement, polarization and electric...

Using principle of minimum total potential energy approach in conjunction with Rayleigh-Ritz method, the electro-thermo-mechanical axial buckling behavior of piezoelectric polymeric cylindrical shell reinforced with double-walled boron-nitride nanotube (DWBNNT) is investigated. Coupling between electrical and mechanical fields are considered according to a representative volume element (RVE)-ba...

In this paper, the modified Euler-Bernoulli beam model is presented to examine the influence of surface elasticity and residual surface tension on the critical force of axial buckling of nanotubes in the presence of rotary inertia. An explicit solution is derived for the buckling loads of microscaled Euler beams considering surface effects. The size-dependent buckling behavior of the nanotube d...

It is proposed to identify the behavior of steel beams prior to and after the inception of local buckling by using Digital Image Correlation. Full field measurements are used to evaluate kinematic and static fields for determining constitutive laws. It enables for the detection of local buckling inception and the evaluation of the postbuckled behavior. Constitutive models are tuned by using mea...

Aluminum alloy sheets have several advantages such as the lightweight, high-specific strength and recycling efficiency. Therefore, aluminum alloy sheets in sheet forming have been used in various areas as automotive components and so forth. During the process of sheet forming, wrinkling which is caused by compression stress might occur and the formability of sheets was affected by occurrence of...